16.
8/2/2011 Construction Project
Management, NAC, Hyd
• Embankment- refers to
a volume of earthen
material that is placed
and compacted for the
purpose of raising the
grade of a roadway (or
railway) above the level
of the existing
surrounding ground
surface.
• A fill refers to a volume
of earthen material that
is placed and compacted
for the purpose of filling
in a hole or depression.
material.
embankment

17.
8/2/2011 Construction Project
Management, NAC, Hyd
• EMBANKMENT
• Soil survey and identification of borrow areas
– Height of embankment : 0.6m/1m above the
H.F.L. or ground.
– Rolling by 150 to 300 mm compacted thickness
– Materials free of logs, stumps, roots, rubbish
or any other ingredients , LL<70 and PI<45
– Highly expansive clays only at the bottom of
the embankment, no such material placed nor
permitted to remain in the top 500mm

21.
8/2/2011 Construction Project
Management, NAC, Hyd
To achieve max. dry density: as required
Diff. Between subgrade top and ground level< 500 mm
and ground does not have 97 % relative compaction with
respect to dry density, ground to be loosened upto 500
mm below subgrade and watered and compacted in layers
Spreading materials in layers and bringing to
appropriate moisture content
-to be spread in 200 mm compacted thickness- compacted
and finished with motor grader.
-Moisture content to be checked prior to compaction. If
required to be sprinkled by sprinkler capable of spreading
uniform rate

22.
8/2/2011 Construction Project
Management, NAC, Hyd
Rolling
• motor grader for spreading
• Roller of 8-10T capacity vibratory roller
• Rolling begins from edges with the roller running
forward and backward
• Progress gradually from the edges to centre overlapping
uniformly each preceding rear wheel track by one half
width
• Rolling continue until the road metal thoroughly keyed
with no creeping of metal ahead of the roller
• Slight sprinkling of water
•Rolling not done when the subgrade is soft or yielding or
when rolling causes a wave like motion in the subbase
or subgrade
• Checked transversely by template for camber
• Irregularities corrected

32.
8/2/2011 Construction Project
Management, NAC, Hyd
Moisture Content
As the moisture content increases with the same
compactive effort, the weight of the soil solids in a unit
volume gradually increases.
Beyond a certain moisture content, any increase in the
moisture content tends to reduce the dry unit weight
because water takes up the spaces that would have been
occupied by the solid particles.
Moisture content at which the maximum dry unit weight is
attained - optimum moisture content (OMC), when the
degree of saturation equals 100%.

35.
8/2/2011 Construction Project
Management, NAC, Hyd
Effect of Compaction Effort: Amount of Compactive
Effort
Compaction energy per unit volume (E) used for the
standard proctor test is described as follows: E = [ (No of
blows/layer) x (No of layers) x (weight of hammer) x (drop
height of hammer) ] / Volume of the mould.
If the compactive effort per unit volume is altered, the
moisture unit weight curve is also altered. As the
compaction effort increases, the maximum dry unit weight
of compaction also increases.
In addition, the increase in compaction effort also causes
the optimum moisture content to decrease to some extent.

54.
8/2/2011 Construction Project
Management, NAC, Hyd
Lateral Confinement of Aggregates
• Construct side shoulders in advance
• Inside edges may be trimmed vertical
• Included area cleaned off all spilled materials
Spreading of Aggregates
• Uniformly and evenly spread
• Twisting motion to avoid segregation
• Proper profile by using templates
• Surface of the aggregate spread trued up and all
high or low spots remedied by removing or adding
aggregate

55.
8/2/2011 Construction Project
Management, NAC, Hyd
Rolling
• Immediately after spreading, compacted to the full
width by rolling with either a three wheel power roller
of 8- 10T capacity or an equivalent vibratory
roller
• Rolling begins from edges with the roller running
forward and backward
• Adding screenings simultaneously until edges
compacted
• Progress gradually from the edges to centre
overlapping uniformly each preceding rear wheel
track by one half width
• Rolling continue until the road metal thoroughly
keyed with no creeping of metal ahead of the roller
• Slight sprinkling of water

56.
8/2/2011 Construction Project
Management, NAC, Hyd
• Rolling not done when the subgrade is soft or
yielding or when rolling causes a wave like
motion in the subbase or subgrade
• Checked transversely by template for camber
• Irregularities corrected
• In no case use of screenings to make up
depressions permitted
CONSTRUCTION STEPS- WBM

58.
8/2/2011 Construction Project
Management, NAC, Hyd
Sprinkling and Grouting
• Copiously sprinkling with water, swept and rolled
• Sprinkling, sweeping and rolling operation continued
and additional screenings applied
• Till a grout is formed of screenings and water that
will fill all voids and form a wave of grout ahead of
the wheels of the roller

59.
8/2/2011 Construction Project
Management, NAC, Hyd
Application of Binding Material
• Suitable binding material applied at a uniform and
slow rate in two or more successive thin layers
• Copiously sprinkled with water and resulting slurry
swept in with hand brooms or mechanical brooms so as to
fill the voids properly
• Surface then rolled by a 8-10 tonne roller
• Spreading of binding material, sprinkling of water,
sweeping with brooms
• Rolling continue until the slurry that is formed
forms a wave ahead of wheels of moving roller

60.
8/2/2011 Construction Project
Management, NAC, Hyd
Setting and Drying
• Allowed to dry over night
• Next morning uneven spot filled with screening
or binding material sprinkled with water if
necessary
• Rolled
• No traffic allowed on the road until this has set

69.
8/2/2011 Construction Project
Management, NAC, Hyd
To plug the capillary voids
To coat and bond loose materials on the
surface
To harden or toughen the surface
To promote adhesion between granular and
the bituminous layer
PURPOSE OF PRIMING

73.
8/2/2011 Construction Project
Management, NAC, Hyd
Purpose of Tack Coat:
To ensure a bond between the new
construction and the old surface
Use of Cutback:
It should be restricted for sites at
subzero temperatures or for emergency
applications
TACK COAT

75.
8/2/2011 Construction Project
Management, NAC, Hyd
Weather & seasonal limitations
bituminous primer should not be applied on
a wet surface or during dust
strom,weather is foggy rainy and windy
when emulsion is used then surface can be
damp but no standing water
CONSTRUCTION

76.
8/2/2011 Construction Project
Management, NAC, Hyd
Shall be clean and free from dust, dirt
and any extraeous material
Surface shall be swept clean with a
mechanical and
high pressure
air jet
PREPARATION OF BASE

82.
8/2/2011 Construction Project
Management, NAC, Hyd
FAILURES IN PAVEMENTFAILURES IN PAVEMENT
• Major are two in category
– Fatigue
• Fatigue cracking - series of interconnecting cracks on
the pavement surface caused by repeated traffic
loading
• Fatigue occurs at places of bituminous layer
– Rutting
– It is called permanent deformation because it
represents an accumulation of small amounts of
unrecoverable deformations
– under the channelized repeated wheel loads